Method and apparatus for noninvasive intraductal fluid diagnostic screen

ABSTRACT

Disclosed is a method and apparatus for accomplishing a noninvasive screen for breast disease markers, including breast cancer markers and cytologically abnormal cells. Intraductal fluid is noninvasively aspirated using compression, heating and suction cycles. The removed sample is thereafter assayed for the presence of cytologically abnormal cells and/or one or more breast disease markers. In addition to the diagnostic applications of the disclosed method and apparatus, a therapeutic application is also contemplated wherein intraductal fluids are noninvasively aspirated using compression, heating and suction cycles to remove toxic buildups within the fluid.

This is a continuation-in-part of U.S. patent application Ser. No.09/870,402, filed May 30, 2001, which is incorporated in its entiretyherein by reference.

The present invention relates to methods and devices for conductingnoninvasive screening assays for indicia of breast cancer or otherbreast disease.

BACKGROUND OF THE INVENTION

Breast cancer is by far the most common form of cancer in women, and isthe second leading cause of cancer death in humans. Despite many recentadvances in diagnosing and treating breast cancer, the prevalence ofthis disease has been steadily rising at a rate of about 1% per yearsince 1940. Today, the likelihood that a woman living in North Americawill develop breast cancer during her lifetime is one in eight. Thecurrent widespread use of mammography has resulted in improved detectionof breast cancer. Nonetheless, the death rate due to breast cancer hasremained unchanged at about 27 deaths per 100,000 women. All too often,breast cancer is discovered at a stage that is too far advanced, whentherapeutic options and survival rates are severely limited.Accordingly, more sensitive and reliable methods are needed to detectsmall (less than 2 cm diameter), early stage, in situ carcinomas of thebreast. Such methods should significantly improve breast cancersurvival, as suggested by the successful employment of Papinicolousmears for early detection and treatment of cervical cancer.

In addition to the problem of early detection, there remain seriousproblems in distinguishing between malignant and benign breast disease,in staging known breast cancers, and in differentiating betweendifferent types of breast cancers (e.g. estrogen dependent versusnon-estrogen dependent tumors). Recent efforts to develop improvedmethods for breast cancer detection, staging and classification havefocused on a promising array of so-called cancer “markers.” Cancermarkers are typically proteins that are uniquely expressed (e.g. as acell surface or secreted protein) by cancerous cells, or are expressedat measurably increased or decreased levels by cancerous cells comparedto normal cells. Other cancer markers can include specific DNA or RNAsequences marking deleterious genetic changes or alterations in thepatterns or levels of gene expression associated with particular formsof cancer.

A large number and variety of breast cancer markers have been identifiedto date, and many of these have been shown to have important value fordetermining prognostic and/or treatment-related variables. Prognosticvariables are those variables that serve to predict disease outcome,such as the likelihood or timing of relapse or survival.Treatment-related variables predict the likelihood of success or failureof a given therapeutic plan. Certain breast cancer markers clearly serveboth functions. For example, estrogen receptor levels are predictive ofrelapse and survival for breast cancer patients, independent oftreatment, and are also predictive of responsiveness to endocrinetherapy. Pertschuk et al., Cancer 66: 1663-1670, 1990; Parl and Posey,Hum. Pathol. 19: 960-966, 1988; Kinsel et al., Cancer Res. 49:1052-1056, 1989; Anderson and Poulson Cancer 65: 1901-1908, 1989.

The utility of specific breast cancer markers for screening anddiagnosis, staging and classification, monitoring and/or therapypurposes depends on the nature and activity of the marker in question.For general reviews of breast cancer markers, see Porter-Jordan et al.,Hematol. Oncol. Clin. North Amer. 8: 73-100, 1994; and Greiner,Pharmaceutical Tech., May, 1993, pp. 28-44. As reflected in thesereviews, a primary focus for developing breast cancer markers hascentered on the overlapping areas of tumorigenesis, tumor growth andcancer invasion. Tumorigenesis and tumor growth can be assessed using avariety of cell proliferation markers (for example Ki67, cyclin D1 andproliferating cell nuclear antigen (PCNA)), some of which may beimportant oncogenes as well. Tumor growth can also be evaluated using avariety of growth factor and hormone markers (for example estrogen,epidermal growth factor (EGF), erbB-2, transforming growth factor(TGF).alpha.), which may be overexpressed, underexpressed or exhibitaltered activity in cancer cells. By the same token, receptors ofautocrine or exocrine growth factors and hormones (for example insulingrowth factor (IGF) receptors, and EGF receptor) may also exhibitchanges in expression or activity associated with tumor growth. Lastly,tumor growth is supported by angiogenesis involving the elaboration andgrowth of new blood vessels and the concomitant expression of angiogenicfactors that can serve as markers for tumorigenesis and tumor growth.

In addition to tumorigenic, proliferation and growth markers, a numberof markers have been identified that can serve as indicators ofinvasiveness and/or metastatic potential in a population of cancercells. These markers generally reflect altered interactions betweencancer cells and their surrounding microenvironment. For example, whencancer cells invade or metastasize, detectable changes may occur in theexpression or activity of cell adhesion or motility factors, examples ofwhich include the cancer markers Cathepsin D, plasminogen activators,collagenases and other factors. In addition, decreased expression oroverexpression of several putative tumor “suppressor” genes (for examplenm23, p53 and rb) has been directly associated with increased metastaticpotential or deregulation of growth predictive of poor disease outcome.

Thus, the evaluation of proliferation markers, oncogenes, growth factorsand growth factor receptors, angiogenic factors, proteases, adhesionfactors and tumor suppressor genes, among other cancer markers, canprovide important information concerning the risk, presence, status orfuture behavior of cancer in a patient. Determining the presence orlevel of expression or activity of one or more of these cancer markerscan aid in the differential diagnosis of patients with uncertainclinical abnormalities, for example by distinguishing malignant frombenign abnormalities. Furthermore, in patients presenting withestablished malignancy, cancer markers can be useful to predict the riskof future relapse, or the likelihood of response in a particular patientto a selected therapeutic course. Even more specific information can beobtained by analyzing highly specific cancer markers, or combinations ofmarkers, which may predict responsiveness of a patient to specific drugsor treatment options.

Methods for detecting and measuring cancer markers have beenrevolutionized by the development of immunological assays, particularlyby assays that utilize monoclonal antibody technology. Previously, manycancer markers could only be detected or measured using conventionalbiochemical assay methods, which generally require large test samplesand are therefore unsuitable in most clinical applications. In contrast,modern immunoassay techniques can detect and measure cancer markers inrelatively much smaller samples, particularly when monoclonal antibodiesthat specifically recognize a targeted marker protein are used.Accordingly, it is now routine to assay for the presence or absence,level, or activity of selected cancer markers by immunohistochemicallystaining breast tissue specimens obtained via conventional biopsymethods. Because of the highly sensitive nature of immunohistochemicalstaining, these methods have also been successfully employed to detectand measure cancer markers in smaller, needle biopsy specimens whichrequire less invasive sample gathering procedures compared toconventional biopsy specimens. In addition, other immunological methodshave been developed and are now well known in the art which allow fordetection and measurement of cancer markers in noncellular samples suchas serum and other biological fluids from patients. The use of thesealternative sample sources substantially reduces the morbidity and costsof assays compared to procedures employing conventional biopsy samples,which allows for application of cancer marker assays in early screeningand low risk monitoring programs where invasive biopsy procedures arenot indicated.

For the purpose of breast cancer evaluation, the use of conventional orneedle biopsy samples for cancer marker assays is often undesirable,because a primary goal of such assays is to detect the cancer before itprogresses to a palpable or mammographically detectable tumor stage.Prior to this stage, biopsies are generally contraindicated, makingearly screening and low risk monitoring procedures employing suchsamples untenable. Therefore, there is general need in the art to obtainsamples for breast cancer marker assays by less invasive means thanbiopsy.

Thus, serum withdrawal has been attempted for breast cancer markerassays. Efforts to utilize serum samples for breast cancer marker assayshave met with limited success. The targeted markers are either notdetectable in serum, or telltale changes in the levels or activity ofthe markers cannot be monitored in serum. In addition, the presence ofbreast cancer markers in serum may occur at the time ofmicro-metastasis, making serum assays less useful for detectingpre-metastatic disease. In contrast, fluid within the mammary glandsthemselves is expected to contain much higher and more biologicallyrelevant levels of breast cancer markers than serum, particularly inview of the fact that 80%-90% of all breast cancers occur within theintraductal epithelium of these glands. Fluid within the breast ducts isexpected to contain an assemblage and concentration of hormones, growthfactors and other potential markers comparable to those secreted by, oracting upon, the surrounding cells of the alveolar-ductal system.Likewise, mammary fluid is expected to contain cells and solid cellulardebris or products that can be used in cytological or immunologicalassays to evaluate intracellular or cell surface markers that may not bedetectable in the liquid fraction of mammary fluid.

Previous attempts to develop non-invasive breast cancer marker assaysutilizing mammary fluid samples have included studies of mammary fluidobtained from patients presenting with spontaneous nipple discharge. Inone of these studies, conducted by Inaji et al., Cancer 60: 3008-3013,1987, levels of the breast cancer marker carcinoembryonic antigen (CEA)were measured using conventional, enzyme linked immunoassay (ELISA) andsandwich-type, monoclonal immunoassay methods. These methodssuccessfully and reproducibly demonstrated that CEA levels inspontaneously discharged mammary fluid provide a sensitive indicator ofnonpalpable breast cancer. In a subsequent study, also by Inaji et al.,Jpn. J. Clin. Oncol. 19: 373-379, 1989, these results were expandedusing a more sensitive, dry chemistry, dot-immunobinding assay for CEAdetermination. This latter study reported that elevated CEA levelsoccurred in 43% of patients tested with palpable breast tumors, and in73% of patients tested with nonpalpable breast tumors. CEA levels in thedischarged mammary fluid were highly correlated with intratumoral CEAlevels, indicating that the level of CEA expression by breast cancercells is closely reflected in the mammary fluid CEA content. Based onthese results, the authors concluded that immunoassays for CEA inspontaneously discharged mammary fluid are useful for screeningnonpalpable breast cancer.

Although the evaluation of mammary fluid has been shown to be a usefulmethod for screening nonpalpable breast cancer in women who experiencespontaneous nipple discharge, the rarity of this condition renders themethods of Inaji et al, inapplicable to the majority of women who arecandidates for early breast cancer screening. In addition, the firstInaji report cited above determined that certain patients sufferingspontaneous nipple discharge secrete less than 10 μl of mammary fluid,which is a critically low level for the ELISA and sandwich immunoassaysemployed in that study. It is likely that other antibodies used to assayother cancer markers may exhibit even lower sensitivity than theanti-CEA antibodies used by Inaji and coworkers, and may therefore notbe adaptable or sensitive enough to be employed even in dry chemicalimmunoassays of small samples of spontaneously discharged mammary fluid.

In view of the above, an important need remains in the art for morewidely applicable, non-invasive methods and devices for obtainingbiological samples for use in evaluating, diagnosing and managing breastdisease including cancer, particularly for screening early stage,nonpalpable breast tumors. Biological samples thus obtained can be usedto evaluate, diagnose and manage breast disease, particularly bydetecting or measuring selected breast cancer markers, or panels ofbreast cancer markers, to provide highly specific, cancer prognosticand/or treatment-related information, and to diagnose and managepre-cancerous conditions, cancer susceptibility, breast infections andother breast diseases.

SUMMARY OF THE INVENTION

There is provided in accordance with one aspect of the presentinvention, an intraductal fluid sampling system. This system comprises acontrol unit, and a patient interface unit. A control line extendsbetween the control unit and the patient interface unit. A closed fluidcirculation loop has a first component which is removably carried by thecontrol unit, and a second component which is carried by the patientinterface unit. The first component may comprise a reservoir inproximity to a heating unit. In one embodiment, the circulation loopcomprises a movable wall, such as a compressible tube. The secondcomponent comprises a radially movable patient compression structure,such as an inflatable bladder.

In one application of the invention, the bladder comprises at leastabout three inflatable lobes. In one particular device, the bladdercomprises six inflatable lobes.

Each lobe has an inflated width of no more than about 3 inches and aninflated length of no more than about 4 inches. Generally, each lobe hasan inflated width of no more than about 2 inches and an inflated lengthof no more than about 3 inches. Each lobe has an inflated thickness ofno more than about 1 inch, and in one embodiment, each lobe has aninflated thickness of about between 0.8 inches and 1 inch. In otherembodiments, each lobe has an inflated thickness of no more than about0.5 inches.

The intraductal fluid sampling system further comprises a support in thepatient interface unit, for supporting the second component incompressive contact with the patient. Preferably, the support isadjustable. A disposable patient interface may also be provided, forpositioning between the patient interface unit and the patient.

In accordance with another aspect of the present invention, there isprovided an intraductal fluid sampling system. This system comprises acontrol unit, a patient interface unit, a control line extending betweenthe control unit and the patient interface unit, and a flow pathextending along the control line and providing communication between afirst component carried by the control unit and a second componentcarried by the patient interface unit.

Preferably, the flow path comprises a closed circulation loop. The firstcomponent may comprise a reservoir, which may be removably carried bythe control unit. The second component may comprise at least oneinflatable bladder, for providing compressive pressure to the patient.

The system further comprises a support in the patient interface unit,for supporting the second component in compressive contact with thepatient. Preferably, the support is adjustable throughout a range. Thissystem may further comprise a disposable patient interface, carried bythe patient interface unit, for contacting the patient. In oneembodiment, the disposable patient interface comprises a flexiblepolymeric membrane. The disposable patient interface may additionallycomprise a rigid support, for maintaining patency under vacuum, attachedto the flexible polymeric membrane.

Further features and advantages of the present invention will becomeapparent to those of skill in the art in view of the detaileddescription of preferred embodiments which follows, when consideredtogether with the attached drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a portable, self-containedintraductal fluid aspiration device.

FIG. 2 is an illustration of a portable self-contained intraductal fluidaspiration device as in FIG. 1, schematically illustrating a pluralityof annular compression rings.

FIG. 3 is a schematic illustration of a desktop or cart top embodimentof an intraductal fluid aspiration device in accordance with the presentinvention.

FIG. 4 is a schematic illustration of a sample collection patch, incommunication with the flow path between the patient and a vacuumsource.

FIG. 5 is an isometric illustration of another embodiment of anintraductal fluid aspiration power head.

FIG. 6 is an illustration of an intraductal fluid aspiration power headas in FIG. 5, from a rear isometric view.

FIG. 7 is an exploded view illustration of the components of anintraductal fluid aspiration power head.

FIG. 8 is a cross-sectional view taken along the line 8—8 of FIG. 5.

FIG. 9 is an illustration of one embodiment of an inflatable bladder foruse with an intraductal fluid aspiration power head.

FIG. 10 a is an illustration of a release mechanism for use inconjunction with an intraductal fluid aspiration power head.

FIG. 10 b is an illustration of a release mechanism in a disengagedposition.

FIG. 11 is an illustration of one embodiment of a patient interface foruse with an intraductal fluid aspiration power head.

FIG. 12 is an illustration of one embodiment of a self-containedintraductal fluid aspiration device.

FIGS. 13A and 13B illustrate the petal range of motion demonstrating aninitial starting position and a rough adjusted position.

FIGS. 14A and 14B illustrate the varying diameter of the patientinterface between a deflated and inflated state of the inflatablebladder of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, there is illustrated a schematic representation ofa portable, self-contained intraductal fluid aspiration device 20 inaccordance with one aspect of the present invention. The aspirationdevice 20 includes a housing 22, for containing various controls andfunctional components of the device 20. One or more controls and/orindicators 25 may be provided on the housing, for controlling variousaspects of the device such as suction, compression, and other features(e.g., heat, ultrasound) which may be included depending upon theintended functionality of the aspiration device 20. The housing 22 maybe formed by extrusion, injection molding or other well known techniquesfrom a suitable biocompatible material such as high densitypolyethylene, nylon, polyethylene terephthalate, or others well known inthe art. The housing is preferably formed in an ergonomic configuration,to comfortably facilitate grasping in one hand during use.

The housing 22 is provided with a patient or breast interface 24, whichmay either be permanently attached to the housing 22 or removablyattached such as for cleaning or disposal. Breast interface 24 has aproximal end 26, a distal end 28, and a body 30 extending therebetween.The interface 24 has a tissue contacting surface 32 defining a firstconcavity 34 for receiving a breast and a second concavity 38 forreceiving a nipple. The tissue contacting surface 32 may be an integralsurface on the body 30, or may comprise a separate interior liner whichis adhered to or otherwise fit within and/or secured to the body 30.

The body 30 may be manufactured in any of a variety of ways, such asinjection molding, blow molding tube stock within a tapered capturetube, or other known manners, using any of a variety of well knownbiocompatible polymeric materials. Preferably, the body 30 istransparent, which may be achieved by forming from polycarbonate, orother relatively clear materials known in the art. In one embodiment,the generally frusto-conical body 30 is sufficiently rigid to providesupport for a flexible interior liner.

The dimensions of the interface 24 may be varied widely, as will beappreciated by those of skill in the art in view of the disclosureherein. In general, the distal end 28 of the flexible body 30 isprovided with an elastic sealing ring 35 having an inside diameterwithin the range of from about 2″ to about 10″. The distal limit of thesecond concavity 38 has an inside diameter within the range of fromabout 1″ to about 4″. The first concavity 34 has an axial length fromproximal end 26 to distal end 28 within the range of from about 0″ toabout 12″, and, in many embodiments, within the range of from about 2″to about 6″. The first concavity 34 has a generally conical or bellshaped interior configuration, as will be appreciated by those of skillin the art.

Preferably, the breast interface 24 is provided with a dynamiccompression zone 42, having one or more compression elements 45 forcompression in the mid breast region to facilitate intraductal fluidaspiration. Although the specific dimensions will vary from patient topatient, as well as with age and parity, the breast includes a pluralityof ducts which are generally confluent in the direction of a pluralityof external openings on the nipple. Most of the intraductal volume iscontained in the distal one-half or one-third of the breast (from thepatient's perspective). Thus, the inventors presently believe that acompression zone approximately centered around the midbreast region inan average patient and extending anatomically distally will optimizefluid transport in the duct.

Referring to FIG. 2, the dynamic compression zone 42 is schematicallyillustrated (not to scale) as comprising a plurality of annularcompression rings 44, 46, 48 and 50. Preferably, the annular compressionrings are in operative communication with a driver 52 in the housing 22,to permit sequential operation. One operation mode mimics a peristalticmotion such that tissue compression is accomplished sequentiallyproximally with respect to the device starting with compression ring 44followed by compression ring 46 followed by compression ring 48 followedby compression ring 50. As will be apparent to those of skill in the artin view of the disclosure herein, any of a wide variety of compressionring numbers and configurations may be utilized in accordance with thepresent invention. Thus, the illustration of four compression rings inFIG. 2 is not considered limiting on the scope of the invention. Ingeneral, anywhere from about one to about twenty compression elements 45may be utilized, in ring form or nonannular form, and, preferably,between about three and ten are contemplated in most embodiments.

The compression elements 45 may comprise any of a variety of structures,such as inflatable tubular elements or other inflatable structures, ormechanical compression elements such as rollers. In the illustratedembodiment, which is not drawn to scale in order to improve clarity, thedynamic compression zone 42 comprises a plurality of annular,inflatable, tubular compression rings each of which is connected to thedriver 52 by a unique conduit 56. The driver 52 preferably includes amicroprocessor or other central processing unit for sequentially drivingthe compression elements 45 as described previously. In one embodiment,the driver 52 includes a pump for controllably inflating and deflatingeach compression ring in response to the microprocessor and inaccordance with the predetermined compression protocol. Inflation mediasuch as air, water, or gel may be utilized, depending upon the desiredperformance characteristics. In one embodiment, a heat retaining gelsuch as morphing gel, available from Dow Corning, is utilized to enablethe delivery of heat during the compression cycle.

The compression elements 45 may alternatively be connected to each otherby a capillary tube or flow restriction orifice, or pressure reliefvalves to enable compression (inflation) in a predetermined sequence.Alternatively, the compression elements 45 may be in fluid communicationwith each other, with each having a wall with a unique durometer orelasticity such that each element inflates as a unique thresholdinflation pressure is reached and/or exceeded.

The microprocessor may be programmed to a particular pumping andcompression cycle characteristic, or may be adjustable by the user tooptimize the aspiration function as desired. For example, compressioncycles may be peristaltic, with a sequential compression pattern fromchest wall (distal end 28) to the proximal end 26. Alternatively, thecompression cycle may be non peristaltic pulsatile. Vacuum may beapplied constantly throughout the pumping cycle, or may be pulsatileeither in phase or out of phase with the compression cycles.

The aspiration device 20 is further provided with a vacuum generatorsuch as a pump in the housing 22, in communication with the secondconcavity 38 by way of a vacuum conduit (not shown). Associatedelectronics, such as a power source and driving circuitry are preferablyconnected to a control 25 to enable the user to selectively activate anddeactivate the vacuum. Alternatively, the pump and vacuum functions maybe fully automatic, and pre-programmed into the micro-processor. Thepump is generally capable of generating a vacuum within an operatingrange of from 0 (pump off) to about 300 mm/Hg. Although vacuum in excessof 300 mm/Hg may also be utilized, vacuum in this area or higher maycause rupture of microvasculature and is unnecessary to accomplish theobjectives of the present invention. For this reason, limit valves maybe provided in communication with the vacuum conduit, as are known inthe art, to limit the vacuum to no more than about 200 mm Hg, or 250 mmHg, or 300 mm Hg. Within the methods of the invention, negativepressures of 50-200 mm Hg are preferred, and these pressures aremaintained, preferably intermittently, for approximately 1-15 minutes,depending on the sensitivity of individual patients, oxytocin dosage andother factors.

The foregoing embodiment is useful in a variety of settings,particularly for in-home intraductal aspiration. In an alternativeembodiment of the present invention, a desk top, or mobile cart top,unit 60 is provided, such as for the physician's office or otherconventional clinical setting. See FIG. 3. The desk top intraductalfluid aspiration system 60 comprises a control unit 62, in communicationwith one or more power heads 64 by way of an elongate flexible controlline 66. The power head 64 is provided with a disposable user interface68 which may be similar or identical to the interface 24 describedpreviously. In this embodiment, the interface 68 is preferably removablyconnected to the power head 64, to facilitate one time use andsubsequent disposal of the interface 68. Alternatively, the entireinterface and power head assembly may be one time use disposable.

The control 62 preferably includes the vacuum pump, and other drivercircuitry and controls as may be needed depending upon the intendedfunctionality of the desk top unit 60. For example, a vacuum pump (notillustrated) is in communication with the disposable user interface 68by way of a vacuum lumen (not illustrated) extending throughout thelength of the control line 66. Additional lumens or wiring extendthrough the control line 66 for accomplishing the peristaltic or othersequential compression motion of the dynamic compression zone 42 as hasbeen discussed.

In either a diagnostic or non-diagnostic embodiment, a sample collectoror reservoir may be positioned in fluid communication with thedisposable user interface 68, to allow collection of intraductal fluid.The sample collector or container may be removable, such as to enabletransport of collected intraductal fluid to a diagnostic laboratory orother facility for diagnostic analysis.

Preferably, the disposable user interface 68 is provided with a heatsource, such as a heat retaining gel or other media for surrounding orcontacting the interface 24, and/or for inflating the compressionelements as has been previously discussed. Alternatively, resistanceheating elements may be provided in the disposable user interface 68 orassociated power head 64, powered by way of electrical conductorsextending throughout the control line 66. In an embodiment where thedynamic compression zone 42 includes elements filled with a heatretaining gel or other media for retaining heat, the breast interface 24may be removed and heated such as in a microwave oven or other heatsource prior to use. An ultrasound source may also be provided in thecontrol unit 62 or power head 64, for driving one or more ultrasoundtransducers in the power head 64 to assist in initial removal of keratinplugs that may occur at the opening of the ducts, and possibly also toserve as a heating source. Alternatively, a heating fluid may becirculated through a closed loop such as from a heater in the controlunit 62, through a first lumen in control line 66 to a heat exchanger inthe power head 64 or patient interface, and back through a second lumenin control line 66 to the control unit 62.

The volume of expressed mammary fluid will vary depending on a varietyof factors, including patient sensitivity to oxytocin, if used, dosageof oxytocin delivered, time and pressure and other variables of breastpump administration, and other factors. For certain relatively lowsensitivity breast marker assays, a volume of expressed mammary fluid of300-500 μl is preferred to provide ample material for conducting theassay, and these volumes are expected to be obtainable from asubstantial proportion of women treated according to the above methods.To express 300-500 μl of mammary fluid, some women will require repeatedstimulation treatments, perhaps requiring pooling of mammary fluidsamples obtained during multiple patient visits. However, for moresensitive assays of the invention, e.g. solid phase immunoassays, muchsmaller samples of 3 μl or less may be sufficient to carry out theassays. This is particularly so in the case of breast cancer markersthat are naturally secreted into the mammary fluid and are thereforeexpected to be present in very high concentrations compared to, forexample, breast epithelial cell surface antigens or intracellularantigens that may not be secreted.

Although one aspect of the present invention lies in the novel,noninvasive methods for obtaining biological samples from mammary fluid,an additional aspect of the invention involves the use of the collectedsample for detecting and/or measuring important breast disease markers.The invention thus enables the convenient application of a broad rangeof assay methods incorporating known procedures and reagents fordetermining the presence and/or expression levels of breast diseasemarkers, particularly breast cancer markers, in biological samples.

During or after the mammary fluid expression step, a biological sampleis collected from the expressed mammary fluid. A range of suitablebiological samples are contemplated and will be useful within themethods of the invention, including whole mammary fluid, selected liquidor solid fractions of the mammary fluid, whole cells or cellularconstituents, proteins, glycoproteins, peptides, nucleotides (includingDNA and RNA polynucleotides) and other like biochemical and molecularconstituents of the mammary fluid.

Sample collection can be achieved simply by receiving the expressedmammary fluid within a suitable reservoir such as within or incommunication with the concavity 38 with or without an absorptive samplecollection media. Samples can be collected directly on to orsubsequently exposed to conventional buffers, diluents, extraction orchromatographic media, filters, etc., to stabilize or prepare the samplefor further processing or direct incorporation into a desired assay. Incertain embodiments of the invention, the expressed mammary fluid iscollected directly onto a solid phase medium, such as a microscopicglass slide, nitrocellulose filter, affinity column, dot blot matrix,cotton swab, or other like medium, that will selectively adsorb, bind,filter or otherwise process desired components of the mammary fluid,such as bulk or selected proteins, for convenient incorporation into adesired assay.

Alternatively, the sample may be collected from the patient's skin usingany of the collection devices disclosed herein, following removal of thepatient interface. The relatively high viscosity of the NAF sample tendsto allow the sample to adhere to the patient's skin where it can beconveniently collected.

Referring to FIG. 4, a flow path such as lumen 39 draws collected fluidfrom the patient through a sample collection patch 41. The samplecollection patch 41 may be positioned directly against the externalopening of the ducts, to minimize fluid loss in the device.

In the illustrated embodiment, the sample collection patch 41 ismoveably positioned within the flow path, with a mild biasing force inthe distal direction. In this manner, the patch 41 can maintain lowpressure contact with the distal surface of the nipple throughout arange of axial positions along the longitudinal axis of the patientinterface. Preferably, an axial range of motion is provided for at leastthe tissue contacting portion of the patch 41 of at least about 0.25inches. In some embodiments, the range of from about 0.5 inches to about2 inches or more may be accomplished. In the illustrated embodiment, theaxial motion of the sample collection patch 41 is achieved by allowingbending or pivoting of the patch 41, throughout the patch and/or at areleasable attachment point 43 to either the patient interface 24 or thehousing 22. Axial movement of the sample collection patch mayalternatively be accomplished by mounting the sample collection patch onthe surface of a compressible foam, which will compress in response topressure from the patient. Alternatively, the compressible foam may formthe sample collection media, without a separate patch, as is describedbelow.

The sample collection patch 41 or other sample collection media may beremovably attached to the aspiration device 20 such as by one or morereleasable connections 47, which may comprise adhesive surfaces ormechanical interfit surfaces such as an annular recess for receiving thepatch 41, radially inwardly extending tabs for receiving the patch 41,or others as will be apparent to those of skill in the art in view ofthe disclosure herein. The patch 41 may consist entirely of a flexibleabsorptive medium. Alternatively, the patch may include an absorptivemedium in combination with a support structure such as a backing plate,or an annular ring for surrounding the patch 41, and facilitatingreleasable connection to the aspiration device 20.

The patch 41 is preferably removable from the aspiration device 20. Thepatch 41 may be removed through the first concavity or chamber 34, byhand or using tweezers, hemostats or other retrieval device.Alternatively, the patch 41 may be removed through a lateral opening 49in the side wall of the aspiration device 20. As a further alternative,the patch 41 may be removed following disconnection of the patientinterface 24 from the housing 22.

The patch 41 or distal surface of a solid sample collection medium suchas a foam may have any of a variety of configurations, depending uponother aspects of the device design. In the illustrated embodiment, thepatch 41 is a generally planar membrane. Alternatively, the patch 41 orpatient contacting surface of a solid foam or other collection devicemay be conical or otherwise concave in the direction of the patient. Thesample collection patch 41 or other sample collection structure may alsohave a component which extends distally towards the patient, from alower portion of the patch 41, to capture any sample which may dropunder the influence of gravity without first being absorbed by the patch41.

The fluid capacity of the patch 41 or other collection media may bevaried, depending upon the intended patient population and purpose ofthe aspiration. In general, sample sizes in the microliter or lowmilliliter range may be useful for different types of assays. For acertain patient populations, the volume of fluid expressed may reach inexcess of 1 to 5 milliliters or greater, in which case a fluidcollection chamber may be provided on the device in the area of theillustrated opening 49 on FIG. 4. Any of a variety of such variationswill be apparent to those of skill in the art in view of the disclosureherein, taking into account the purpose of the aspiration.

The composition and construction of sample collection patch 41 willvary, depending upon the nature of the intended assay. For example, anyof a wide variety of porous or absorptive materials may be utilized tocollect cellular and cellular component samples which may be used forcytological exam. Materials such as conventional filter paper, cottongauze, fiber webs such as knitted fabrics or nonwoven rayon or cellulosefibers may be used. A variety of microporous films comprising materialssuch as nylon 66, polycarbonate, modified polyvinyl fluoride andpolyether sulfone may alternatively be used. Embodiments of thecollection patch 41 which are intended to permit chemical or biochemicalassays may additionally be provided with any of a variety of binders foreither chemically binding with an analyte or adsorbing the analyte to bedetermined. The binder layer may additionally include a specific bindingpartner of the analyte to be determined, such as a polyclonal ormonoclonal antibody or an antigen matched to a specific antibody desiredto be measured in the extracted fluid. Other binding systems which arematched to the desired analyte or analytes may be readily adapted foruse in the present invention, as will be understood by those of skill inthe art. The range of contemplated sample collection procedures andmaterials that are useful within the invention is broad, and selectedmethods and materials will vary with each selected assay, as will beunderstood and readily practiced by those skilled in the art.

The sample collection patch may be constructed of any suitable material.In preferred embodiments, the sample collection patch includes amembrane or filtration medium upon, through, or in which a fluid sampleis collected. The sample collection patch may be of any suitable shape.While circular or square patches are preferred for many applications,other shapes may also be used. The sample collection patch should be ofsufficient size such that an adequate sample may be collected.

The sample collection patch may include a material capable of providingdepth filtration or sieve filtration of a sample. In depth filtration,particulates are trapped both within the matrix and on the surface ofthe filtration medium. Depth filters are composed of random mats ofmetallic, polymeric, inorganic, or organic materials. Depth filters relyon the density and thickness of the mats to trap particulates andfluids, and generally retain large quantities of particulates or fluidswithin the matrices. Certain disadvantages of depth filters includemedia migration, which is the shifting of the filter medium understress, and particulate unloading at high differential pressures.Advantages of depth filters include reduced cost, high throughputs, highvolume-holding capacity, removal of a range of particle sizes, and highflow rates.

In sieve filtration, particulates larger than the pore size of amembrane are trapped, while smaller particulates pass through themembrane but may be captured within the membrane by some othermechanism. Sieve filtration membranes are generally polymeric filmsapproximately 120 microns thick with a narrow pore size distribution.Certain disadvantages of sieve filtration include lower flow rates andlower particulate holding capacity. Advantages include absolutesubmicron pore size ratings, no channeling or bypass, capacity forretaining bacteria and particles, low extractables, sterilizable, andintegrity testable.

In various embodiments, the sample collection patch includes one or morefiltration media such as the filtration media manufactured by PallGelman Sciences of East Hills, N.Y. Such filtration media that may besuitable for use in particular assays of the various embodiments includefiltration media originally developed for use in blood separations. Suchfiltration media may include polyester filtration media such as PallGelman's Hemasep™ modified polyester materials, polyether sulfonemembranes such as the Presense™ membrane, Cytosep® single layer fibercomposite membrane, and Leukosorb® medium. Other suitable filtrationmedia may include the Predator™ membrane, a polyether sulfone membranethat is surface modified to possess nitro groups.

Pall Gelman's Biodyne® nylon 6,6 membranes may also be suitable for usein sample collection patches for certain assays. Unmodified Biodyne®nylon 6,6 membrane may be preferred for some applications.Alternatively, the Biodyne® nylon 6,6 membrane may be surface modifiedwith quaternary ammonium groups so as to impart a positive charge to thepore surfaces, thereby promoting strong ionic bonding of negativelycharged analytes. Likewise, the Biodyne® nylon 6,6 membrane may besurface modified with carboxyl groups so as to impart a negative chargeto the pore surfaces, thereby promoting strong ionic bonding ofpositively charged analytes. Such carboxyl group surface-modifiedBiodyne® nylon 6,6 membranes may be derivatized via coupling reactionsthrough the carboxyl groups at the pore surfaces.

In various embodiments other membranes may be preferred for use insample collection patches, such as Biotrace® nitrocellulose membranes,Fluorotrans® polyvinylidene difluoride (PVDF) membranes, Immunodyne® ABCnylon 6,6 affinity membranes having a high density of covalent bindingsites capable of permanently immobilizing proteins and peptides oncontact, and Ultrabind™ aldehyde-modified polyether sulfone membranescapable of providing covalent binding to amine groups on proteins.

Various absorbent materials also available from Pall Gelman may also beused in certain embodiments, such as conjugate pads comprised ofborosilicate glass with no binder or with polyvinylacetate (PVA) oranother suitable binder, Loprosorb™ low protein binding hydrophilicfibrous medium, cellulose absorbent papers, Loprodyne® internallysupported nylon 6,6 membrane with low protein binding, or Z-Bind™post-treated modified polyether sulfone membrane.

Ion exchange membranes may be preferred for use in sample collectionpatches for certain assays. Such membranes may include Pall Gelman'sRaipore™ ion-exchange polytetrafluoroethylene (PTFE) cationic or anionicmembranes, and microporous ion exchange membranes constructed ofpolyether sulfone and possessing either sulfonic acid or quaternaryammonium groups on the membrane surface.

In various applications, it may be preferred to use a hydrophobic and/oroleophobic material in a sample collection patch. Materials suitable foruse in such applications may include Pall Gelman's Hydrolon® nylon 6,6membranes, Hydrolon® PTFE membranes, Supor® R polyethersulfone membrane,and Pallflex composite materials.

The above-mentioned filtration media available from Pall Gelman arerepresentative examples of the wide variety of commercially availablefiltration media that may be suitable for use in sample collectionpatches. Various filtration media available from other manufacturers mayalso be suitable for use in sample collection patches, as maycustom-manufactured filtration media. Suitable filtration media mayinclude a single material, e.g., a single membrane, or may be acomposite manufactured from two or more materials, e.g., variouscombinations of membranes, woven and nonwoven support materials, wovenand nonwoven filtration media, barrier materials, and other materials.The sample collection patch may further include additional substances,such as reagents, buffers, probes, surfactants, binders, indicators,preservatives, and the like, such as may be useful in performing variousassays.

Such filtration media may be bonded to a flexible structure, spring orother support to allow movement in and out of the collection chamber andto also allow ease of removal of the material for sample handling andremoval. Alternatively, a closed-cell foam structure may be substitutedfor such media, thereby allowing movement in the chamber whilemaintaining contact with the nipple, either as a stand-alone collectionmedium or with a membrane bonded at the surface of the medium. Suchmedia may also act as contamination barriers, protecting the powerheadcircuit and pump system in the control console from contamination bybody fluids in the negative pressure air path.

Thus, the present invention provides a method of screening intraductalbreast fluid for one or more breast disease markers. The methodcomprises the steps of contacting the breast with a mechanicalintraductal fluid aspiration device, and activating the device to applycompression and suction to the breast during a period of nonlactation toremove intraductal breast fluid. The fluid is thereafter screened suchas by cytological examination and/or biochemical screening for breastdisease markers. In one embodiment, the method further comprises thestep of applying heat from the device to the breast.

There is also provided an intraductal breast fluid screening device. Thedevice comprises a tissue contacting surface defining a first concavityfor receiving a breast and a second concavity for receiving a nipple. Adriver for imparting compressive force on at least a portion of thetissue contacting surface defining the first concavity is additionallyprovided. A vacuum conduit is provided in communication with the secondconcavity, and a sample collector may be provided in communication withthe second concavity. The sample collector may be a reservoir, or anabsorptive patch for absorbing or retaining a sample. Preferably, thecollection patch is removable from the aspiration device.

The required sample size may vary, depending upon the intended assay orscreening test. For example, relatively larger fluid volumes will berequired for cytological examination as is well understood in the art.Relatively smaller sample sizes may suffice for monoclonal antibody orother specific binding chemistry assays or biochemical markers.

Referencing FIG. 5, an alternative embodiment of an intraductal fluidaspiration power head 100, or patient interface unit, in accordance withone aspect of the present invention is illustrated. The power head 100is preferably formed in an ergonomic configuration to comfortablyfacilitate grasping in one hand during use and comprises a support suchas a plurality of adjustable petals 126 that define an adjustable firstconcavity 164 for receiving a breast. There are generally between abouttwo and about twenty petals, preferably, between four and eight petals,and six petals are present in one embodiment. The petals 126 arehingedly or otherwise movably connected to the main body (132 of FIG. 7)and are operatively coupled to a slide collar 134 via pinned links 136or pivots.

A control is provided, to enable rough sizing of the device toaccommodate a range of patient sizes. In the illustrated embodiment, thecontrol comprises an adjustment ring 140. The slide collar 134 iscarried by the adjustment ring 140, which is threaded onto the main body(132 of FIG. 7). As the adjustment ring 140 is rotated onto the mainbody 134, it translates linearly in a longitudinal direction 168. Theslide collar 134 is in sliding engagement with the adjustment ring 140such that the slide collar 134 does not rotate as the adjustment ring140 is twisted about the main body 132.

In operation, the adjustment ring 140 is manually rotated about the mainbody, which causes the slide collar 134 to translate in a linear,longitudinal direction 168, thereby displacing the links 136, whichcause the petals to pivot inward or outward about their connection pointto the main body.

The support may take any of a variety of forms, and still accomplish theintended functional objective of providing support against which amovable element, such as an inflatable bladder (discussed below), willapply compressive pressure to the breast. Thus, the support may take theform of a rigid conical or hemispherical structure, or a flexiblestructure, such as a woven material or relatively inelastic polymericwall. In general, however, the support is preferably adjustable in sizeto accommodate any of a wide variety of patients.

The illustrated support is one manner in which adjustability can beachieved. Alternatively, any of a variety of structures which allow theinside diameter of the distal opening of the support to be radiallyenlarged or reduced may be utilized. For example, the wall of thesupport may include a helical spring or other element which, when adistal end is rotated or otherwise manipulated relative to a proximalend, a radial reduction or enlargement is achieved. Alternatively, aflexible strap or band, such as a woven fabric, may be wrapped aroundand attached to itself using any of a variety of fasteners, such as hookand loop (e.g., Velcro®), snaps, or other fasteners known in the art.This construction is known in currently available blood pressure cuffs.

The foregoing structures take into account the usual circumstance thatthe range of inflation of the inflatable bladder as discussed below willgenerally be smaller than the range in patient sizes. Thus, the supportcan be rough adjusted so that the patient interface may be fitted to thepatient with the inflatable bladders deflated, thereby ensuring thatinflation of the inflatable bladders or other compression structure willaccomplish a sufficient compression and minimize patient to patientperformance variability. Additional details of the inflatable bladderswill be discussed below.

The power head 100 is further provided with a patient interface 154,which may either be permanently attached to the power head 100 orremovably attached such as for cleaning or disposal. In at least oneembodiment, as shown in FIG. 11, patient interface 154 is a disposablesheath and includes a flexible frustoconical portion 248, or membrane,made of any of a variety of well known biocompatible polymeric materialssuch as silicone or any of a number of well known styrene blockcopolymers sold under the trade name Kraton, manufactured by KratonPolymers. Examples of suitable materials may include, but are notlimited to, styrene-butadiene-styrene (SBS),styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene-styrene(SIS), or styrene-ethylene-propylene (SEP). Suitable polymers preferablyexhibit a very low modulus of elasticity, allowing the material tostretch several times its original length, and a relatively high tearstrength and optionally transparency, thus allowing an operator to seeinto the device to properly position a breast therein. The polymer ispreferably bondable to polycarbonate or polypropylene, and is glutinouswhen contacted with certain materials thus allowing it to grip thepetals 126 when mounted, while not adhering to latex, thereby allowingan operator wearing latex gloves to easily handle the patient interface154.

The flexible portion 248 defines the tissue contacting surface 156 andis supported by the petals 126 which define the first concavity 164. Thepatient interface 154 is further configured with a relatively rigidproximal portion 250 configured to fit within the second concavity 166.The rigid portion 250 may be sized to receive a nipple, and has aninside diameter within the range of from about 0.5 inches to about 4inches, and in one embodiment, has a length of about 1.5 inches and adiameter at its distal end of about 1.5 inches.

The rigid portion 250 terminates proximally at a tip 254 which has alumen formed therein for allowing a vacuum conduit 160 to be in fluidcommunication with the interior of the patient interface 154. Theproximal tip 254 may optionally contain a microbarrier for inhibitingcontaminants from entering the patient interface 154 or being aspiratedthrough the vacuum conduit 160. Moreover, the rigid portion 250 maycarry a sample collection patch or other sample collector for collectingthe aspirated fluid sample as has been discussed. The rigid portion 250may be formed of a transparent, or semi-transparent, polymer such as,for example, polycarbonate or polypropylene to allow an operator tovisually verify the position of the device on a patient. The removablepatient interface 154 is removably connected to or otherwise fit withinand/or secured to the power head 100.

Thus, in accordance with the disposable patient interface aspect of thepresent invention, there is provided a disposable patient interface foran intraductal fluid aspiration device. The interface comprises asealing component and a vacuum chamber component. In the illustratedembodiment, the sealing component comprises a flexible tubular membrane,having a proximal end, a distal end and a passageway extendingtherethrough. The proximal end has a smaller cross-sectional area thanthe distal end, defining a generally frustoconical structure. A rigidproximal cap is provided on the proximal end of the flexible tubularmembrane, and contains the vacuum chamber. A vacuum port is provided onthe cap for connection to a source of vacuum.

The proximal cap 250 defines a chamber therein, and the cap exhibitssufficient structural integrity that it resists collapse when a vacuumof at least about 6 mm Hg is applied to the chamber. Preferably, theproximal cap 250 exhibits sufficient rigidity that it resists collapsewhen a vacuum of at least about 100 mm Hg is applied to the chamber.

The unstressed diameter of the distal end of the flexible tubularmembrane 248 is generally within the range of from about 1 inches toabout 6 inches, although other sizes may be utilized depending upon thedesired clinical performance and intended patient population. Generally,the unstressed diameter of the distal end is no more than about 4inches. The diameter of the distal end may be stretched to at leastabout 150% of its unstressed diameter without rupturing the membrane.Preferably, the diameter of the distal end may be stretched to at leastabout 200%, and, in some embodiments, as much as 400% or more of itsunstressed diameter without rupturing the membrane.

In one application of the invention, the tubular member comprises astyrene block copolymer, having a wall thickness of no more than about0.05 inches, and, in many embodiments, a wall thickness of no more thanabout 0.015 inches.

The axial length of the tubular membrane 248 from the distal end of theproximal cap to the distal end of the tubular membrane, along thesurface of the membrane, is generally within the range of from about 1inch to about 6 inches and, in many embodiments, within the range offrom about 2 inches to about 4 inches.

In one embodiment, the proximal cap 250 comprises at least a firstretention structure for releasable connection with a complementarysecond retention structure on the patient interface 154. The firstretention structure may comprise a recess on the proximal cap or aprojection on the proximal cap, and may be in the form of an annularbead or recess on the proximal tip 254.

In one embodiment, as shown in FIG. 5, the flexible portion 248 isstretched to fit over the distal periphery of the petals 126, andsecured about a lip 190 formed on the outside surface of the petals. Thepatient interface 154 thus spans the gap between the individual petals126 and thereby provides a flexible biobarrier to inhibit patient tissuefrom being pinched between the adjustable petals 126. The rigid portion250 is removably mounted and snap fit or otherwise retained within thesecond concavity 166 as will be discussed in greater detail hereinafter.

Referring generally to FIGS. 5 and 6, an inflatable bladder 152 conformsto the radially inwardly facing walls of at least the first concavity164, and is sandwiched between the petals 126 and patient interface 154.The inflatable bladder 152 is preferably configured to receive aninflation media, thereby inflating and effectively reducing the volumewithin at least the first concavity 164, thereby applying a compressiveforce to a breast positioned therein. The specifics of the inflatablebladder will be discussed in greater detail hereinafter.

Referencing FIG. 6, the power head 100 is shown from a rear isometricview. From this perspective, the control tubes 160, 162, and 172 areillustrated. A vacuum conduit 160 is in communication with the interiorchamber in the patient interface 154. In the illustrated embodiment, thevacuum conduit 160 passes through a tube grommet 146 and is supportedthereby. The tube grommet 146 provides bending support to the vacuumconduit 160 and helps protect the tube from crimping or kinking. Itfurther provides a fitting for receiving the distal tip 254 of the rigidmounting portion 250 of the patient interface 154, as will be shown anddescribed hereinafter.

A pair of inflation conduits 162, 172, enter the power head 100 and arein fluid communication with the inflatable bladder 152 therein. Theinflation conduits 162, 172 may be configured to cooperate in a varietyof ways. For example, both conduits may deliver and subsequentlywithdraw inflation media to the bladder; each conduit may serve anisolated inflation chamber within the bladder; or one inflation conduit162 may deliver inflation media, while the other conduit 172 maywithdraw inflation media. The inflation media may be any gas, liquid,gel, or other media suitable for inflating the inflatable bladder 152.In an embodiment in which a heat source is provided remotely from thepower head 100, the inflation media preferably also exhibits good heattransfer characteristics. Deionized water appears to have suitableperformance. The inflation conduits 162, 172, are preferably formed of amaterial capable of withstanding hoop stress such that the inflationpressure inflates the inflatable bladder 152 rather than expands theinflation conduits 162, 172.

A release ring 148 is provided to release the patient interface from itsmounted location and may optionally release the seal between the patientinterface 154 and the patient upon completion of the intraductal fluidaspiration procedure, and will be discussed in greater detail inreference to FIGS. 10 a and 10 b. Alternatively, the vacuum releasefunction may be assigned to the control unit.

Turning to FIG. 7, an exploded view of the power head components isshown. For ease in describing the interrelation between the constituentcomponents, they will be described in the context of assembly. Many ofthe following described features become more readily apparent in FIG. 8,and therefore, that figure is also referenced in relation to thefollowing description.

The main body 132 has a plurality of petal mounting flanges 124 on itsdistal end, each having a threaded hole formed therein for receiving athreaded fastener 130, and at least one face groove 174 for receiving aportion of a petal 126. A plurality of petals 126 are provided eachhaving an integral mounting pin 176 configured to fit within the facegroove 174 formed into each petal mounting flange 124. A plurality ofpetal retainers 128 mount to the face of each petal mounting flange 124to thereby secure the petal mounting pins 176 within the face grooves174. In this manner, the petals 126 are hingedly mounted to the mainbody 132 and are pivotal about petal mounting pins 176. However, othermethods of pivotal or bondable connection, such as through a compliantmechanism, may be used as should be apparent to those of ordinary skillin the art in light of the disclosure herein. This pivotal attachmentallows for the power head 100 to be size-adjustable to fit differentpatients.

An adjustment ring 140 has a knurled portion 182 at a proximal end andan annular ridge 178 at a distal end. The knurled portion 182 provides anon-tangential surface for gripping to ease in threading the adjustmentring 140 on the main body 132. The annular ridge 178 cooperates with anannular groove 180, or equivalent structure, formed along the insidediameter of the slide collar 134 to engage the two components whileinhibiting their disassembly. It is preferable that the adjustment ring140 is free to easily rotate independent of the slide collar 134 duringadjustment, and for this reason, materials exhibiting a relatively lowcoefficient of friction are used. Polymers and elastomers such aspolybutylene terephthalate (PBT), acrylonitrile butadiene styrene (ABS),polyethylene, polypropylene, and polyurethane are preferred because oftheir high strength to weight ratios, low electrical conductivity, andability to receive lubricant and colorant additives into their basicresins. Another benefit of using such materials is that they can beprocessed from raw materials into a final size, shape, and finishthrough any one of several basic casting operations, including injectionmolding, while maintaining the ability to be machined through anystandard chip-producing, material-removal process to create details notavailable through standard casting processes. Additional components,such as the petals 126, main body 132, and links 136 are also preferablyfabricated of similar materials to take advantage of these properties.

The main body 132 has outer body threads 122 formed thereon forcooperating with internal threads 188 of the adjustment ring 140. Byrotating the adjustment ring 140 about the main body 132, the adjustmentring 140, and accompanying slide collar 134 are linearly translated. Themain body 122 has one or more longitudinal grooves 123 that cooperatewith corresponding tabs 133 inside the slide collar 134 to prevent theslide collar 134 from rotating about the main body 122. During assembly,the slide collar tabs 133 are inserted into the main body grooves 123such that the tabs track within the grooves 123 and prevent subsequentrotation of the slide collar 134 relative to the main body 122. Theslide collar 134 is coupled to mounting ribs 184 formed on the petals126 via pinned links 136. The mounting ribs 184 are spaced to flank thelink 136, and have a hole formed therethrough for receiving a pin 138.Likewise, the links 136 are hingedly attached to the slide collar 134 atmounting ribs 186. The pivotal mounting can be effected in any of anumber of ways, and is not limited to a pin 138 as shown.

As the adjustment ring 140 is threaded about the main body 132, theattached slide collar 134 translates linearly, which imparts a linearmotion to the links 136 which, in turn, causes the petals 126 to pivotabout their attachment points. In this manner, the first concavity 164is adjustable throughout a range between an initial open position, andan adjusted, patient form-fitting, position. In one embodiment, thepetals are moveable between a fully open position, wherein the petalsare substantially co-planar to each other and perpendicular to thelongitudinal direction 168, and a fully closed position, wherein thepetals 126 come together and contact along their edges, extendinggenerally in parallel to the longitudinal axis. Thus, the minimum volumeencompassed by the petals 126 is constrained only by the specific petalgeometry. The petals 126 can be shaped such that the minimum volume ofthe first concavity 164 is substantially smaller than that achievable bythe illustrated petal design.

For example, FIG. 8 illustrates one embodiment of a petal design whereineach petal is identically sized and shaped. For example, each petal isabout 2 in. wide in the transverse direction 170 by 1.75 in. high in thelongitudinal direction 168, and is shaped such that it is concaveinwardly in both a longitudinal 168 and transverse 170 direction. Inthis manner, the cooperating petals define a first concavity 164 that issubstantially bowl or bell-shaped. The petals 126 could be sized andshaped differently to provide a more individual fit. For example, thepetals 126 could be shaped and/or arranged to provide a substantiallyoval first concavity 164. Additionally, one or more petals 126 may befixedly attached, with the remainder adjustable, or one or more petals126 may exhibit different travel characteristics to result in variousform-fitting shapes. Four, or three or two (e.g. clam shellconfiguration) petals may also be used, depending upon the desiredmanufacturing cost and clinical performance.

It is the adjustability of the first concavity 164, defined by therelative orientation of the plurality of petals 126 or other adjustablesupport structure, that allows the device to be adjustable to allow asingle device to accommodate a range of patient sizes, to provide acomfortable fit and help create a seal between the power head 100 andthe patient in order to effectively carry out the aspiration procedure.

The dimensions and adjustability range of the first concavity 164 may bevaried widely, as will be appreciated by those of skill in the art inview of the disclosure herein. In general, the distal opening defined bythe distal limit of the petals 126 has an adjustable diameter within therange of from about 2 inches to about 12 inches. The adjustability isillustrated in reference to FIGS. 13A and 13B wherein the diameter “D”is adjustable within the range of from about 2 inches (D₁) to about 12inches (D₂), and in certain embodiments, within the range of from about3½ inches to about 6.5 inches. The second concavity 166 has an insidediameter within the range of from about 1 inches to about 4 inches. Thefirst concavity 164 has an axial length within the range of from about 0inches to about 12 inches, and, in many embodiments, within the range offrom about 0 inches to about 6 inches. The first concavity 164 has agenerally conical, hemispherical or bell shaped contoured interiorconfiguration, as previously described, as will be appreciated by thoseof skill in the art.

Referring briefly to FIGS. 14A and 14B, when the device is adjusted tofit a patient, for example, the inside diameter of the first cavity 164is further movable between a first, large diameter D₃ when the bladder152 is deflated and a second, reduced diameter D₄ when the bladder 152is fully inflated. Diameters may be measured from a geometricalmid-point 233 on a first petal to a geometrical mid-point 233 on asecond, opposing petal, as a reference. The difference between D₃ and D₄provides an indication of the fully inflated thickness in the radialdirection of the opposing lobes 152 of the bladder. In many embodimentsof the present invention, the difference D₃-D₄ is within the range offrom about 0.25 inches to about 2.5 inches. Generally, the differenceD₃-D₄ is within the range of from about 12 inch to about 1½ inches. Aswill be appreciated by those of skill in the art, a D₃-D₄ difference of1 inch means that the patient contacting surface of each opposingbladder lobe is movable throughout an operating range of about 0.5inches.

Returning to FIG. 8, and with supplemental reference to FIG. 7, a tubesupport 144 is secured to the main body 132 by any suitable manner, suchas threaded fasteners, and provides a support for the control tubes 160,162, 172 extending therethrough. Tube support 144 additionally carries atube grommet 146 which provides additional support to the vacuum conduit160 as previously described. A release ring 148 is provided to disengagethe patient interface rigid portion 250 from its mounted location. Therelease ring may optionally be used to release the vacuum seal betweenthe patient interface 154 and patient. The purpose and operation of therelease ring 148 and related components will be discussed in greaterdetail in connection with FIGS. 10 a and 10 b.

Referencing FIGS. 5 and 9, an inflatable bladder 152 is configured tofit at least within the first concavity 164. The main body 132 includesindexing structures such as one or more mounting tabs 102 (of FIG. 8)which position the inflatable bladder 152 toward the outer circumferenceof the main body 132. Furthermore, the inflation conduits 162, 172 passthrough holes formed in the main body (132 of FIG. 6) and experiencesliding friction therewith such that once the inflatable bladder 152 ispositioned within the power head 100 and the inflation conduits 162, 172are passed through the main body 132, the inflatable bladder 152 isinhibited from being dislodged from its desired position by theresistance of the inflation conduits 162, 172 from being slidablydisplaced. The inflatable bladder 152 is in fluid communication withinflation conduits 162, 172, and in one embodiment, one conduit isconfigured to deliver inflation media while the other conduit isconfigured to return inflation media.

In one aspect, the inflatable bladder 152 is configured to include aplurality of lobes 204, each corresponding to a petal 126, and may beoptionally mounted thereto by adhesives, interference fit structures orother effective mounting methods. The lobes 204 are preferably generallyrounded into a generally pear shape to allow the lobe to maintain afairly uniform stress when under pressure. Each lobe 204 in theillustrated embodiment is sized to contain between about 1 mL and 100 mLof inflation media, and more particularly, to contain between about 5 mLand 20 mL. In one embodiment, the lobes 204 each have an inflated volumeof about 10 ml, and have profile dimensions such that when fullyinflated they extend radially inwardly through a thickness of about 1.0inches.

In general, when the lobes 204 are fully inflated, they protrudeinwardly between about 0.2 inches and about 2 inches from the inner wallof the petals 126, and in one embodiment, between about 0.75 inches andabout 1.5 inches. Aside from the first and last lobe, 206 and 208respectively, the outlet 210 of one lobe 204 connects to the inlet 212of an adjacent lobe 204. Although in the illustrated embodiment, aplurality of lobes 204 are connected sequentially in series, parallelflow paths or other configurations are possible as described herein.

The inflation conduit 162 is securely attached to the inlet 212 of thefirst lobe 206 at 214 by any suitable manner, such as heat welding, byadhesives, crimping, and the like, and delivers inflation media to thefirst lobe 206 at a predetermined flow rate. In one embodiment, theinflatable bladder 152 is formed in a single die cut and heat weldingstep out of a material amenable to these techniques, such as, forexample, polyurethane film having a thickness between about 0.003 inchesand 0.030 inches. In one embodiment, a polyurethane film thickness of0.015 inches is preferred. The inflation conduits 162, 172 may bepermanently attached, such as by heat welding, during this singlefabrication step. The inflation media is allowed to flow through theremaining lobes 204 and out through the final lobe 208, which terminatesin a return conduit 172. The conduits 162, 172 may also be sealed to areservoir, discussed below, to provide the closed loop. The closed loopmay be charged with inflation media at the point of manufacture.

The return conduit 172 may have at least a portion that presents asmaller diameter for the media to flow through, thereby creating anamount of back pressure in the fluid system. Any of a variety of flowrestrictors, such as apertures or reduced diameter flow paths may beused. In one embodiment, the return conduit 172 has a smaller insidediameter than the inflation conduit 162; however, the conduits 162, 172could share a common diameter and a fitting along the return conduit 172could include a portion having a diameter smaller than the inflationconduits 162, 172. In an alternative embodiment, a check valve may beplaced along the return flow path 172 thereby allowing an adjustablerestrictor for varying the back pressure which adjusts the inflationpressure. Additionally, an adjustable restrictor, such as a duck-billflap, will allow the return path flow to be varied, including blockingthe return flow path completely thereby causing a reverse inflationmedia flow to deflate the inflatable bladders 204 once the pump 262 isturned off. The flow restrictor may be located anywhere along the returnpath 172, including at the exit of the final bladder 208 or at the inletof the fluid reservoir 260. Alternatively, the return conduit 172 couldbe constricted by external forces to reduce the flow therethrough andincrease pressure in the upstream system. As a pump increases the flowof inflation media through the closed fluid system, the return line actsas a restrictor against which the pump creates pressure to inflate thelobes 204.

Thus, in accordance with the disposable fluid loop aspect of the presentinvention, there is provided a closed loop heating and/or compressionsystem for a nipple fluid aspiration device. The closed loop systemcomprises a plurality of inflatable bladders or lobes for providingcompression of a breast, a reservoir, and at least one fluid flow pathfor placing the bladders in fluid communication with the reservoir. Asused herein, the bladder may be referred to either as a multiple lobedbladder, or a plurality of bladders in communication with each other,and/or a common inflation source, without any intended distinction.

In the illustrated embodiment, the fluid flow path comprises a movablewall, such as a compressible tube or reservoir. This allows forcedcirculation such as by exposing the tubing to a roller or platen pump,or by compressing the reservoir. The system generally comprises at leastabout three inflatable bladders, and, in one embodiment, about sixinflatable bladders. Preferably, a heat exchange media, such as a fluidas has been described, is contained within the closed loop. Generally,each bladder has an inflated width of no more than about 3 inches and aninflated length of no more than about 4 inches. In many embodiments,each bladder has an inflated width of no more than about 2 inches and aninflated length of no more than about 3 inches.

The inflated thickness of each bladder may be varied widely, dependingupon the desired performance characteristics. In general, each bladderhas an inflated thickness of no more than about 1 inch, which provides a2 inch dynamic range for the inside diameter of the concavity, duringthe compression and decompression cycles, as is discussed elsewhereherein.

A variety of modifications can be made to the disposable fluid loop, aswill be apparent to those of skill in the art, in view of the structuralsupport aspect of the present invention. In general, the inflatablebladder disclosed herein is one manner of providing a patient interfacesurface which is moveable between a first position in which the cavityhas a relatively large cross sectional dimension and a second positionin which the cavity has a relatively smaller cross sectional dimension.The difference between the relatively large and relatively small crosssectional dimensions of the cavity is the working range of thecompression system.

In an alternate embodiment, the support may be movable throughout theworking range, to provide compression. In this embodiment, the supportmay be moveable through a larger moving range to provide a roughadjustment as has been described elsewhere herein. Once the roughadjustment has been achieved, the support is then moveable throughoutthe smaller compression working range, using any of a variety ofmechanical actuation devices such as a motor drive. In this embodiment,the inflatable bladder may be utilized to circulate a heating media, andnot be utilized to impart compression. Alternatively, the support may beprovided with an alternative heating mechanism such as an internalheating lumen for circulating a heated fluid, or internal electricalresistance coils or other heat source as will be appreciated by those ofskill in the art. In such an embodiment, the inflatable bladder may beentirely eliminated.

An operator of the illustrated intraductal fluid aspiration system candirectly control the inflation pressure of the inflatable bladder 152 byvarying the pump speed. The inflation pressure is controlled by the pumpspeed, due to the flow restriction imposed along the return conduit. Thepump preferably has safety features built in to limit its speed suchthat the inflation pressure provided by the pump cannot exceed the burststrength of the inflatable bladder 152, which in one embodiment, isabout 1000 mm Hg. Alternatively, limit valves may be provided incommunication with the inflation conduits 162, 172, as is known in theart. The operating pressure within the inflatable bladders during thecompression cycle preferably does not exceed about 1000 mm Hg, and morepreferably does not exceed about 420 mm Hg.

Referring back to FIG. 5, the inflatable bladder 152 creates acompression zone to facilitate intraductal fluid aspiration. Asdescribed, the inflatable bladder 152 is preferably in operativecommunication with an external inflation driver (not shown) through oneor more inflation conduits 162, 172. In one embodiment, the inflatablebladder 152 has a single inflation chamber and is operable between adeflated state and a fully inflated state in which the interior pressureof the inflation media reaches a constant pressure. In anotherembodiment, a plurality of discrete inflation chambers are providedwithin the inflatable bladder 152 and are selectively inflated to createvarious compression modes. In one embodiment, the compression modemimics a peristaltic motion such that tissue compression is accomplishedsequentially proximally. This may be accomplished by selectivelyinflating a plurality of inflation chambers in fluid communication witheach other, with each having a wall with a unique durometer orelasticity such that each inflation chamber inflates as a uniquethreshold inflation pressure is reached and/or exceeded. Alternatively,a plurality of inflation chambers may be interconnected in series byvalves that open at sequentially greater pressures thereby sequentiallyinflating the chambers as the inflation pressure increases.

By inflating the inflatable bladder 152, the volume within the first andsecond concavities 164, 166 is effectively reduced, thereby applying acircumferential compressive force to a breast positioned therein. Theinflatable bladder 152 is configured such that the compressive force isapplied at a location that is anatomically adjacent or proximal to apatient's lactiferous sinus. Thus, the geometric center of each lobe isgenerally positioned no more than about three inches from the distal tipof the nipple. In this way, the intraductal fluid is encouraged to flowanatomically distally and is therefore expressed.

As discussed above, the inflation pump may be programmed to a particularcompression cycle characteristic, or may be adjustable by the clinicianto optimize the aspiration function as desired. For example, compressioncycles may be peristaltic, with a sequential compression pattern fromthe patient's chest wall to an anatomically distal end. Alternatively,the compression cycle may be non peristaltic cycles, and may bepulsatile within each cycle. In one embodiment, a roller pump providespulsatile inflation of the inflatable bladder 152 at a pulse ratebetween about 50 and 600 cycles per minute, which may add to thepatient's comfort during the procedure.

The inflation cycle may be sinusoidal having a period of between about 1and 20 cycles per minute. In one application of the invention, eachcompression cycle lasts about 10 seconds from empty to empty. A tensecond pulse with a sinusoidal wave form thus produces approximately 6inflation cycles per minute. Inflation cycles per minute may range fromabout one to about 20 or 30 cpm. In another embodiment, there may be asingle inflation cycle during the aspiration procedure in which theinflatable bladder 152 is inflated under pulsatile pressure throughoutthe procedure. It should be readily apparent to those of ordinary skillin the art that various inflation cycle modes could be substituted forthose described herein without departing from the scope of the claims.

In one embodiment, the inflation conduits 162, 172 are part of a closedfluid loop which includes a fluid reservoir (260 of FIG. 12), a firstinflation conduit 162, the inflatable bladder 152, and a secondinflation conduit 172. In referring to a closed fluid loop, it is to beunderstood that the term “fluid” means any gas, liquid, or gel suitablefor use as inflation media. The same is true when referring to inflationfluid. The closed fluid system is thereby easily removed from the systemand replaced and may be disposed of as desired. Furthermore, a closedfluid system provides convenience in setup and operation of theintraductal fluid aspiration system in addition to patient and devicesafety by keeping the fluid confined.

Inflation media such as gas, liquid, or gel may be utilized dependingupon the desired performance characteristics. In one embodiment, a heatretaining gel such as morphing gel, available from Dow Corning, isutilized to enable the delivery of heat during the compression cycle. Inanother embodiment, deionized water is used as the inflation media,which offers a low electrical conductivity and resists algae andbacteria growth.

In cooperation with the applied compression, a vacuum is created byfirst forming a seal between the patient interface 154 and the patient.Generally, the rigid portion 250 creates a concavity for receiving anipple and contacts the patient at a circumscribing location thereto. Anexternal vacuum generator, such as a pump (230 of FIG. 12), applies anegative pressure in the second concavity 166 through a vacuum conduit160, which removes any trapped air within the concavities 164, 166,thereby creating a vacuum therein and securely sealing at least therigid portion 250 to the patient. Vacuum may be applied constantlythroughout the pumping cycle, or may be pulsatile either in phase or outof phase with the compression cycles.

The pump 230 is generally capable of generating a vacuum within anoperating range of from 0 (pump off) to about 260 mm Hg. Although vacuumin excess of 260 mm Hg may also be utilized, vacuum in this area orhigher may cause rupture of microvasculature and is unnecessary toaccomplish the objectives of the present invention. For this reason,limit valves may be provided in communication with the vacuum conduit,as are known in the art, to limit the vacuum to no more than about 150mm Hg, or 200 mm Hg, or 250 mm Hg. Within the methods of the invention,negative pressures of 150-250 mm Hg are preferred, and these pressuresare maintained, for approximately 1-15 minutes, depending on thesensitivity of individual patients, oxytocin dosage and other factors.The pressure may be maintained constantly throughout the aspirationprocedure, or may be pulsatile.

Preferably, the power head 100 is provided with a heat source, such as aheated inflation media for inflating the inflatable bladder 152.Alternatively, resistance heating elements may be provided in the petals126 and/or patient interface 154, powered by way of electricalconductors extending throughout the power head 100. In an embodimentwhere the patient interface 154 is filled with a heat retaining gel orother media for retaining heat, the patient interface 154 may be removedand heated such as in a microwave oven or other heat source prior touse. An ultrasound source may also be provided remotely or in the powerhead 100, for driving one or more ultrasound transducers in the powerhead 100 to assist in initial removal of keratin plugs that may occur atthe opening of the ducts, and possibly also to serve as a heatingsource.

Alternatively, the inflation media may be circulated through a heater264, through a first inflation conduit 162 into the inflatable bladder152, and back through a second inflation conduit 172 to maintain anelevated inflation fluid temperature within the inflatable bladder 152.By circulating heated fluid through the closed loop the temperature (andinflation pressure) within the inflatable bladder 152 may beconveniently controlled. Preferably, temperatures in the range of about30° C. to about 55° C., and more preferably within the range of fromabout 37° C. to about 50° C., and in one embodiment, 45° C. aremaintained at the patient contact surface. There is a measurable heatloss as the heated inflation media travels through the inflationconduits 162, 172, and into the inflatable bladder 152, therefore, themedia is preferably heated to a temperature slightly higher thandesired. For example, a 46° C. temperature at the reservoir in oneembodiment of the invention produces a patient contact surfacetemperature of approximately 39.5°-40.5° C. It is believed that theapplied heat may lower the viscosity of the intraductal fluid inaddition to overcoming physiological patient resistance to aid in fluidaspiration.

Referring to FIGS. 10A and 10B, a release ring 148 is provided todisengage the patient interface rigid portion 250 from its mountedlocation. Additionally, the release ring 148 may optionally be used torelease the vacuum created within the second concavity 166 and therebybreak the seal between the patient and patient interface 154. Therelease ring 148 has a handle 218 having a bore therethrough forslideably mounting to a boss 184 of the tube support 144. The releasering 148 is preferably formed of cast polymer as previously describedherein. The release ring 148 has a shelf portion 220 for interactingwith a leaf spring 252 that is cantilevered to the tube support 144. Theleaf spring 252 contacts the shelf portion 220 and biases the releasering 148 in a distal direction. The release ring 148 further includes analignment flange 216 that fits into an alignment slot (not shown) formedin the main body 132 to ensure the proper mating of the constituentcomponents.

The tube support 144 and release ring 148 define an open space forreceiving the rigid portion 250 of the patient interface 154. As thepatient interface 154 is mounted to the power head, the rigid portion250 is pushed into the cavity defined by the tube support 144 andrelease ring 148 until the distal tip 254 enters the vacuum cavity 194(of FIG. 8) formed in the tube grommet 146, and the rigid portion 250 isseated against the tube grommet 146 such that the malleable tube grommet146 compresses against the rigid portion 250 and forms an airtight sealtherewith.

The leaf spring 252 has a concave edge 256 for mating with thesubstantially cylindrical rigid portion 250 of the patient interface154. As the distal tip 254 is forced into the vacuum cavity 194, theconcave edge 256 of the leaf spring 252 contacts a portion along theouter periphery of the rigid portion 250. As the rigid portion 250slides past the leaf spring 252, the leaf spring 252 resiliently bendsin the direction of travel of the rigid portion 250, thus allowing therigid portion 250 to slide by without impeding the movement thereof.Once the rigid portion 250 is mounted, the leaf spring 252 impedes therigid portion 250 from dislodging from its mounted location. The concaveedge 256 of the leaf spring 252 impinges upon the periphery of the rigidportion 250 thereby constructively interfering with the undesiredwithdrawal of the rigid portion 250 from its mounted location. In thisway, the rigid portion 250 of the patient interface 154 is securelymounted thereby creating a substantially airtight seal with the vacuumcavity 194 of the tube grommet 146.

Upon completion of the procedure, the vacuum pressure is released toremove the power head 100 from the patient. This may be accomplished byactuating the release ring 148. As the handle portion 218 of the releasering 148 is manually actuated in a device proximal direction 198, therelease ring shelf 220 elastically deforms the leaf spring 252 such thatthe patient interface rigid portion 250 is no longer constrained in itsmounted location. The patient interface flexible portion 248, by virtueof being stretched to mount over the petals 126, is in tension, suchthat a releasing force is translated to the patient interface rigidportion 250. As the leaf spring 252 is deformed such that it no longercontacts the outer periphery of the patient interface rigid portion 250,the tension from the patient interface flexible portion 248 causes thedistal tip 254 of the rigid portion 250 to withdraw from the vacuumcavity 194 thereby breaking the vacuum seal and allowing the power head100 to be removed from a patient.

Alternatively, the vacuum pressure may be released by a control unitmicroprocessor protocol. For example, the external vacuum pump (notshown) may be configured with a release valve that is selectivelyoperable to interrupt the vacuum. As another alternative, the vacuumpump may be reversible, thereby creating a positive pressure within thesecond concavity 166 further easing the disconnection with the patient.In another embodiment, a valve may be present along the vacuum conduit160, or within the first or second concavities 164, 166, for releasingthe vacuum. It will be apparent to one of skill in the art that thereare a variety of ways to break the vacuum seal that are not disclosedherein yet are contemplated as being within the scope hereof.

Referring to FIG. 12, a self-contained intraductal fluid aspirationdevice is depicted schematically illustrating the components. It shouldbe apparent to one of skill in the art that the device may be a desk topunit, or alternatively stored on a movable cart, such that one devicecan be selectively utilized at various patient treatment locations.Although disclosed with only a single power head 100 for simplicity, thesystem may be provided with two power heads 100 for simultaneousoperation. A control unit 200 houses the apparatuses for deliveringheat, inflation media, and vacuum pressure, in addition to housingfeedback and control devices 266 to allow an operator thereof tocustomize the operational characteristics, such as, for example,temperature, inflation pressure, inflation cycle characteristics, vacuumpressure, vacuum cycle characteristics, and the like. The control unit200 houses a vacuum generator pump 230 for creating a vacuum pressurewithin at least the second concavity 166 of the power head 100 aspreviously described. The vacuum conduit 160 may be permanently attachedto the power head 100, the vacuum generator pump 230, or may beremovably attached to both. In this way, the vacuum conduit 160 may bereplaced as desired.

The control unit 200 further contains a pump 262 for driving thecompression cycle, and in one embodiment, the pump is a three orfour-roller peristaltic pump. The pump 262 is preferably controlled by acontrol circuit, which includes instructions for controlling the pump262 to deliver various modes of operation as described herein. Thecontrol circuit can also include instructions for operating the vacuumgenerating pump 230, and is configured to control the vacuum pressurescreated by the vacuum generating pump 230. The pump 262 is incompressive contact with at least a portion of one of the inflationconduits 162, and imparts a peristaltic pumping action thereto to forceinflation media to flow through the inflation conduit 162. The pump 262may also be reversible to deflate the inflatable bladders 204.

The inflation conduits 162, 172, meet at one end in a fluid reservoir260 that contains a volume of inflation media. The fluid reservoir 260may be a rigid tank, or may be a flexible bag, and may contain a volumewithin the range of from about 50 mL to one liter, and in someembodiments, may contain between about 150 mL and 300 mL, and in oneembodiment, approximately 200 mL. The fluid reservoir 260 is adjacentto, and removably in thermal contact with, a heat exchanger 264 forconducting thermal energy into the inflation media. The heat exchanger264 may be any of a number of known heaters, such as, for example, anelectrical resistance heater. As described above, the inflation media isheated to a temperature within the range of about 30° C. to about 55°C., and more preferably within the range of from about 37° C. to about50° C. To reduce the warm up time prior to use, a secondary, or even atertiary heater may be installed.

The heated inflation media flows through an inflation conduit 172, andinto the inflatable bladder 152 within the power head 100. The inflationmedia may be continuously cycled through the power head 100 and back tothe fluid reservoir 260 for heating.

The inflation conduits 162, 172, inflatable bladder 152, and fluidreservoir 260 form a closed fluid loop, which is preferably removablefrom the system for periodic replacement. To install the fluid loop, thefluid reservoir 260 is inserted into a compartment housed in the controlunit 200, and one of the inflation conduits 162, 172, is positionedacross the pump 262. In this way, the closed fluid loop is isolated fromthe rest of the system and may easily be replaced, if necessary. It alsokeeps the inflation media separate from any electronics that aremoisture sensitive. Hence, the closed fluid loop is not only convenient,but adds an element of safety to the apparatus, the operator, and thepatient. To further protect the sensitive components in the control unit200, bulkheads within the control unit 200 keep the electronics separatefrom the fluid loop.

Thus, according to one aspect of the present invention, a control unitcontains circuitry and hardware for effecting the treatment methodsdisclosed herein. Specifically, a vacuum generator pump, fluidcirculation pump, heat exchanger, and concomitant drivers are providedfor carrying out an intraductal fluid aspiration procedure.

Some embodiments disclosed herein teach the use of a sample collector orreservoir positioned in fluid communication with the patient interface154 to allow collection of intraductal fluid. In other embodiments, theaspirated fluid is allowed to collect on the tissue contacting surface156 of the patient interface 154, with an amount of aspirated fluidlikely to remain on the patient's skin, for subsequent cotton swabcollection.

Additional embodiments may include a fluid detection device for alertingthe operator when a fluid sample has been aspirated. The detectiondevice may be in the form of a conductivity sensor in which theaspirated fluid bridges an electrical gap and completes an electricalcircuit for actuating a visual or audible cue to alert an operator thata fluid sample has been collected. Alternatively, the fluid detectiondevice may comprise a pH strip that will change color or otherwise alertan operator that a fluid sample has been collected.

To perform an intraductal fluid aspiration procedure, a technicianprepares the patient by applying alcohol to remove keratin plugs. Thetechnician determines the approximate size of breast to be tested,either visually, or through patient disclosure. The power head, withattached patient interface, may be rough adjusted to conform to the sizeand/or shape of the breast to be tested. Alternatively, the power headis fully opened to facilitate proper positioning around the nipple.Subsequent to contacting the patient, the power head is adjusted toproperly fit the patient undergoing testing. Preferably, prior tocontacting the patient, the inflation media has been preheated to adesired temperature and the pump idly delivers media flow through thepower head. Once the power head is in contact with the patient and hasbeen properly adjusted, the inflatable bladders receive additionalinflation media and begin compressing the breast. A vacuum may beapplied to at least the nipple to encourage fluid aspiration.

The procedure is anticipated to take approximately between 3 and 20minutes to complete, and more preferably, is anticipated to take no morethan approximately 10 minutes to complete. The procedure is completeupon either (1) collecting a sufficient volume of intraductal fluid, or(2) timing out of the procedure and determining that a sufficient fluidsample cannot be collected during this initiation of the procedure.

Upon procedure completion, the compression is halted and the inflatablebladder is deflated. Additionally, the vacuum is ceased and a vacuumreleasing mechanism is actuated to remove the power head from thepatient. In one embodiment where no sample collection patch is used, thefluid sample will collect on the inner surface of the patient interface,with a volume of fluid likely remaining on the patient for cotton swabcollection. In the alternative, a fluid collection patch may be insertedinto the patient interface such that it maintains contact with thenipple and collects the fluid sample by absorption.

Although the present inventors believe that sufficient sample volumewill be obtainable from most patients using the heat, compression andsuction cycles provided by the pump disclosed herein, some patients maybenefit from administration of one or more agents to enhanceproductivity. For example, oxytocin may be administered, preferably viaintranasal administration, in amounts effective to stimulate mammaryfluid expression in the patient. Once a sufficient post-administrationtime period has elapsed to allow the oxytocin to reach and stimulatetarget alveolar-ductal tissues, the breast is pumped and a biologicalsample is collected, as described above. After the sample is collected,a bioassay is conducted on the sample to determine the presence and/oramount of a selected breast disease marker, preferably a breast cancermarker or panel of breast cancer markers, in the sample.

One additional manner of increasing the collected fluid volume is tointroduce a carrier fluid retrograde into the duct, such as through theuse of a pressurized stream directed to the external opening of theduct. The carrier may alternatively be introduced using an introductionneedle or cannula which is advanced either transluminally through theduct or percutaneously. The carrier fluid may increase mobilization ofcellular fragments and other markers, which will be available uponaspiration of the fluid for assay. Aspiration may occur eitherimmediately following introduction of the carrier fluid, or after asufficient indwelling period of time to permit mobilization of carriersoluble or carrier transportable cells, cell components, or markers.

Any of a wide variety of carriers may be utilized, depending upon thedesired clinical objective. For example, an aqueous solution may beprovided with any of a variety of drugs or other active agents to eithertreat the breast, or facilitate the release and/or transport ofidentifiable markers.

Thus, there is provided in accordance with the present invention amethod of screening for breast cancer or other breast disease,comprising the steps of providing a patient having at least one breastduct with an external opening. A stream of carrier fluid is directedunder pressure into the opening to introduce a volume of carrier fluidinto the duct. The fluid is thereafter removed from the duct through theexternal opening, and the removed carrier fluid is screened for at leastone indicium of a physiological condition such as a marker as discussedin greater detail elsewhere herein. The removing carrier fluid step ispreferably accomplished by the application of suction to the externalopening of the duct. Preferably, suction is accompanied by compressionsuch as peristaltic or other systemic compression. The compressiondevice is preferably heated, such as in accordance with the devicediscussed above. The screening step may be accomplished by screening forcytologically abnormal cells, or markers as discussed in detailelsewhere herein.

Another aspect of the method includes the introduction of a therapeuticspecies into a breast duct, with or without subsequent aspiration formarker assay. In accordance with this method, a media is provided,comprising a carrier and at least one therapeutic species. A stream of amedia is directed at the external opening to the duct, to introducemedia into the duct.

Any of a variety of devices may be utilized, to direct a pressurizedfluid stream. See, for example, U.S. Pat. No. 5,399,163 to Peterson, etal., entitled “Needleless Hypodermic Injection Methods and Device,” thedisclosure of which is incorporated in its entirety herein by reference.Such devices are currently known in the arts of needleless injection andsurgical pressurized water cutting devices, both of which may bemodified to reduce the velocity of the fluid stream so that it isinsufficient to cause tissue damage but sufficient to introduce carrierfluid retrograde into the duct. Introduction may be further facilitatedby optimizing the viscosity and temperature of the fluid carrier, whichmay be accomplished through routine experimentation by those of ordinaryskill in the art in view of the disclosure herein. Powered carrierintroduction is preferably preceded by keratin plug removal, asdiscussed elsewhere herein.

As used herein, the term breast disease marker refers to any cell, cellfragment, protein, peptide, glycoprotein, lipid, glycolipid,proteolipid, or other molecular or biological material that is uniquelyexpressed (e.g. as a cell surface or secreted protein) by diseasedbreast cells, or is expressed at a statistically significant, measurablyincreased or decreased level by diseased breast cells, or in associationwith breast disease (e.g. a protein expressed by an infectious agentassociated with breast disease), or is expressed at a statisticallysignificant, measurably increased or decreased level by diseased breastcells compared to normal breast cells, or which is expressed bynon-diseased breast cells in association with breast disease (e.g. inresponse to the presence of diseased breast cells or substances producedtherefrom). Breast disease markers can also include specific DNA or RNAsequences marking a deleterious genetic change, or an alteration inpatterns or levels of gene expression significantly associated withbreast disease. Preferred breast disease markers include markers ofbreast infections, benign neoplasia, malignant neoplasia, pre-cancerousconditions, and conditions associated with an increased risk of cancer.Breast disease markers include breast cancer markers.

As used herein, the term breast cancer marker refers to a subset ofbreast disease markers, namely any protein, peptide, glycoprotein,lipid, glycolipid, proteolipid, or other molecular or biologicalmaterial that is uniquely expressed (e.g. as a cell surface or secretedprotein) by cancerous cells, or is expressed at a statisticallysignificant, measurably increased or decreased level by cancerous cellscompared to normal cells, or which is expressed by non-cancerous cellsin association with cancer (e.g. in response to the presence ofcancerous cells or substances produced therefrom). Breast cancer markerscan also include specific DNA or RNA sequences marking a deleteriousgenetic change, or an alteration in patterns or levels of geneexpression significantly associated with cancer. In addition, breastcancer markers can include cytological features of whole cells presentin mammary fluid, such as nuclear inclusions or cytoplasmic structuresor staining attributes uniquely expressed by, or associated with,cancerous cells.

Among the breast cancer markers that are useful within the methods ofthe invention, a subset are described in representative review articlesby Porter-Jordan et al., Hematol. Oncol. Clin. North Amer. 8: 73-100,1994; and Greiner, Pharmaceutical Tech, May, 1993, pp. 28-44, eachincorporated herein by reference in its entirety. Other suitable markersare also widely known and can be readily incorporated into the methodsof the invention using information and methods generally known oravailable in the literature. Preferred breast cancer markers for usewithin the invention include well characterized markers that have beenshown to have important value for determining prognostic and/ortreatment-related variables in human female patients. As notedpreviously, prognostic variables are those variables that serve topredict outcome of disease, such as the likelihood or timing of relapseor survival. Treatment-related variables predict the likelihood ofsuccess or failure of a given therapeutic program. Determining thepresence or level of expression or activity of one or more of thesemarkers can aid in the differential diagnosis of patients with malignantand benign abnormalities, and can be useful for predicting the risk offuture relapse or the likelihood of response to a selected therapeuticoption.

It is important to note, however, that the invention does not relysolely on breast disease markers that meet the stringent requirements ofsensitivity and specificity that would render the marker immediatelyacceptable for clinical application to human patients. On the contrary,a number of breast disease markers contemplated within the inventionfall short of these stringent criteria, and nonetheless provide usefulinformation that can be of substantial benefit in detecting,differentially diagnosing or managing breast health including breastcancer. Such non-clinically accepted markers are useful for immediateapplication within the methods of the invention as basic research tools,and as adjunctive tools in clinical applications. Beyond these immediateapplications, many such markers are expected to be further developed andrefined according to the methods of the invention to the point of directclinical applicability, particularly in assay methods that analyzecombinations of markers to generate complementary data of greaterpredictive value than data yielded by individual markers alone.

The preferred assay methods of the invention particularly focus onbreast cancer markers associated with tumorigenesis, tumor growth,neovascularization and cancer invasion, and which by virtue of thisassociation provide important information concerning the risk, presence,status or future behavior of cancer in a patient. As noted previously,tumorigenesis and tumor growth can be assessed using a variety of cellproliferation markers (for example Ki67, cyclin D1 and PCNA). Tumorgrowth can also be evaluated using a variety of growth factor andhormone markers (for example estrogen, EGF, erbB-2, and TGF.alpha.),receptors of autocrine or exocrine growth factors and hormones (forexample IGF and EGF receptors), or angiogenic factors. In addition totumorigenic, proliferation and growth markers, a number of markersprovide information concerning cancer invasion or metastatic potentialin cancer cells, for example by indicating changes in the expression oractivity of cell adhesion or motility factors. Exemplary markers in thiscontext include Cathepsin D, plasminogen activators and collagenases. Inaddition, expression levels of several putative tumor “suppressor”genes, including nm23, p53 and rb, provide important data concerningmetastatic potential, or growth regulation of cancer cells. Assaysdirected to divalent cations, such as Ca²⁺, Zn²⁺, and the like may alsobe helpful in providing important information concerning the risk,presence, status or future behavior of breast cancer. A large number andvariety of suitable breast cancer markers in each of these classes havebeen identified, and many of these have been shown to have importantvalue for determining prognostic and/or treatment-related variablesrelating to breast cancer.

Depending upon the chemistry of any particular assay, the results may beprocessed and expressed in a variety of ways. For example, for certainassays, a color change may be expressed directly from the samplecollection patch in the pump. For other assays, the sample collectionpatch may be removed from the pump and developed in a desk topdeveloping kit which includes whatever reagents, rinse solutions orother materials may be necessary to produce a result. For other assays,the sample collection patch is mailed or otherwise transported to asuitable laboratory for processing.

Prior to or concurrent with each assay run of the invention,particularly in the case of assays preformed at a remote laboratory, apreliminary evaluation may be performed to verify sample origin and/orquality. The focus of such preliminary evaluations is to verify that thesample collected in the collection patch is indeed of mammary origin,and is not contaminated with other potential contaminants, such as sweatfrom skin surrounding the nipple. For these sample verificationpurposes, a variety of assays are available which identify mammary fluidmarkers known to be present in mammalian mammary fluid, and which arepreferably highly specific markers for mammary fluid (i.e. markers whichare typically always present in mammary fluid and which are absent fromall, or most of, other potentially contaminating bodily fluids andtissues).

However, an acceptable level of specificity for mammary fluid markerswithin the methods of the invention is provided by markers that aresimply known to be present in mammary fluid, even though they may bepresent in other bodily fluids. One such marker is the enzyme lysozyme,which is a normal component of human serum, urine, saliva, tears, nasalsecretions, vaginal secretions, seminal fluid, and mammary fluid.Lysozyme (muramidase) is an enzyme which hydrolyzes beta 1,4-glycosidiclinkages in the mucopolysaccharide cell wall of a variety ofmicroorganisms resulting in cell lysis. Quantitative measurement oflysozyme is readily accomplished by a well known agar plate diffusionmethod, described in detail in the instructions provided with theQuantiplate.RTM. lysozyme test kit, available from Kallestad, SanofiDiagnostics (Chasta, Minn.), incorporated herein by reference in itsentirety.

Other mammary fluid markers for sample verification that are morespecific than lysozyme are preferred within the methods of theinvention, and can be readily incorporated within the invention based onpublished and generally known information. The most preferred amongthese markers are proteins and other biological substances that arespecifically expressed or enriched in mammary fluid. A diverse array ofsuitable markers in this context have been characterized and havealready been used to develop specific antibodies, including affinitypurified and monoclonal antibodies. These antibodies can in turn beemployed as immunological probes to determine the presence or absence,and/or to quantify, selected mammary fluid markers to verify mammaryfluid sample origin and quality.

Mammary fluid markers of particular interest for use within theinvention include specific cytokeratins that are characteristicallyexpressed by normal and cancerous mammary epithelial cells, againstwhich specific panels of antibody probes have already been developed.(See for example, Nagle, J. Histochem. Cytochem. 34: 869-881, 1986,incorporated herein by reference in its entirety). Also useful asmammary fluid markers are the human mammary epithelial antigens(HME-Ags) corresponding to glycoprotein components of the human milk fatglobulin (HMFG) protein, against which specific antibodies (e.g. antiHMFG1, Unipath, U.K.) are also available. (see Rosner et al., CancerInvest. 13: 573-582, 1995; Ceriani et al. Proc. Natl. Acad. Sci. USA 74:582-586, 1982; Ceriani et al., Breast Cancer Res. Treat. 15; 161-174,1990, each incorporated herein by reference in its entirety).

To conduct the breast disease marker assays provided within theinvention, a collected biological sample from mammary fluid is generallyexposed to a probe that specifically binds to a selected breast diseaseor breast cancer marker, or otherwise interacts with the marker in adetectable manner to indicate the presence or absence, or amount, of thebreast disease or breast cancer marker in the sample. Selected probesfor this purpose will generally depend on the characteristics of thebreast disease marker, i.e. on whether the marker is a proteinpolynucleotide or other substance. In preferred embodiments of theinvention, the breast disease marker is a protein, peptide orglycoprotein, all of which are effectively targeted in breast diseasemarker assays using specific immunological probes. These immunologicalprobes can be labeled with a covalently bound label to provide a signalfor detecting the probe, or can be indirectly labeled, for example by alabeled secondary antibody that binds the immunological probe to providea detectable signal.

General methods for the production of non-human antisera or monoclonalantibodies (e.g., murine, lagormorpha, porcine, equine) are well knownand may be accomplished by, for example, immunizing an animal with aselected breast disease marker protein, peptides synthesized to includepart of the marker protein sequence, degradation products including partof the marker protein sequence, or fusion proteins including all or partof the marker protein linked to a heterologous protein or peptide.Within various embodiments, monoclonal antibody producing cells areobtained from immunized animals, immortalized and screened, or screenedfirst for the production of an antibody that binds to the selectedbreast cancer marker protein or peptide, and then immortalized.

It may be desirable to transfer the antigen binding regions (i.e.,F(ab′)2 or hypervariable regions) of non-human antibodies into theframework of a human antibody by recombinant DNA techniques to produce asubstantially human molecule. Methods for producing such “humanized”molecules are generally well known and described in, for example, U.S.Pat. No. 4,816,397 (incorporated herein by reference in its entirety).Alternatively, a human monoclonal antibody or portions thereof may beidentified by first screening a human B-cell cDNA library for DNAmolecules that encode antibodies that specifically bind to the selectedbreast disease marker according to the method generally set forth byHuse et al. (Science 246: 1275-1281, 1989 (incorporated herein byreference in its entirety). The DNA molecule may then be cloned andamplified to obtain sequences that encode the antibody (or bindingdomain) of the desired specificity.

Also contemplated within the invention are bifunctional antibodieshaving independent antigen binding sites on each immunoglobulin molecule(as disclosed for example in Thromb. Res. Suppl. X: 83, 1990, and in TheSecond Annual IBC International Conference on Antibody Engineering, A.George ed., Dec. 16-18, 1991; each incorporated herein by reference inits entirety), as well as panels of individual antibodies havingdiffering specificities. Bifunctional antibodies and antibody panels ofparticular use within the invention include antibodies and panels ofantibodies that bind to two or more selected breast disease markers togenerate complementary data of greater predictive value than datayielded by individual markers alone.

Monoclonal antibodies are particularly useful within the invention aslabeled probes to detect, image and/or quantify the presence or activityof selected breast disease markers. In this context, monoclonalantibodies that specifically bind to selected breast disease markers areprovided which incorporate one or more well known labels, such as a dye,fluorescent tag or radiolabel. By incorporating such a label, theantibodies can be employed in routine assays to determine expression,localization and/or activity of one or more selected breast diseasemarkers in a biological sample including, or derived from, mammaryfluid.

Results of these assays to determine expression, localization and/oractivity of a selected breast disease marker in a test sample taken froma patient at risk for breast disease, or known to have breast disease,can be compared to results from control studies detecting and/orquantifying the same marker in biological samples obtained from normalpatients negative for breast disease. In this manner, baseline data andcutoff values can be determined according to routine methods to refinethe assays of the invention and adapt them for direct clinicalapplication.

Detection and/or quantification of breast disease markers in thebiological samples of the invention can be accomplished using a varietyof methods. Preferred methods in this regard include well known ELISAimmunoassays, immunoprecipitation assays, and various solid phaseimmunoassays including Western blotting, dot blotting and affinitypurification immunoassays, among other methods. Comparable methods aredisclosed herein, or are elsewhere disclosed and known in the art, forusing non-antibody probes to detect and/or quantify the expressionand/or activity of breast disease markers. Suitable non-antibody probesfor use within the invention include, for example, labeled nucleotideprobes that hybridize at standard or high stringency to DNA transcriptsof oncogenes and other DNA sequences associated with elevated breastdisease risk, or with mRNA transcripts encoding breast disease markerproteins. Other suitable probes include labeled ligands, bindingpartners and co-factors of breast disease markers (e.g. growth factorreceptor ligands, or substrates of breast cancer associated proteasessuch as Cathepsin D).

In certain embodiments of the invention, cDNA and oligonucleotide probesare employed in Northern, Southern and dot-blot assays for identifyingand quantifying the level of expression of a selected breast diseasemarker in cell samples collected from expressed mammary fluid. Measuringthe level of expression of breast disease markers according to thesemethods will provide important prognostic and treatment-relatedinformation for assessing a broad range of breast disease, including thegenesis, growth and invasiveness of cancer, in mammals, particularlyhumans. For example, assays utilizing oligonucleotide probes will assistearly screening to evaluate heritable genetic lesions associated withbreast cancer, and to distinguish between pre-cancerous, early cancerousand likely metastatic lesions in patients.

In addition to the above mentioned sample extraction, collection andassay methods, the invention also provides kits and multicontainer unitscomprising reagents and components for practicing the sample collectionand assay methods of the invention. Briefly, these kits include basiccomponents for obtaining a biological sample from mammary fluid.

A pharmaceutical preparation of oxytocin in a biologically suitablecarrier may optionally be included. Preferably, the oxytocin preparationis provided in an intranasal spray applicator and contains approximately40 USP units of oxytocin per ml of liquid carrier, which carrier is asimple, inexpensive buffered saline solution. Preferred applicators canbe in any of a variety of pressurized aerosol or hand-pump reservoirforms, with a nozzle for directing a liquid spray of the oxytocin into apatient's nostril.

The breast pump of the present invention is also provided. The pump isdesigned to generate intermittent or sustained negative pressures in anarea surrounding the nipple of between about 50-200 mmHg, as well asheat and compression as has been discussed. Preferably, the breast pumpserves a dual purpose of facilitating mammary fluid expression from thenipple, and to provide the reservoir or solid phase collecting deviceincorporated within the breast pump for biological sample collection.

Kits for practicing the assay methods of the invention include asuitable container or patch or other device for collecting a biologicalsample from expressed mammary fluid. A range of suitable collectiondevices are contemplated corresponding to a wide range of suitablebiological samples that may be collected from the expressed mammaryfluid. For example, simple sterile containers or reservoirs are providedto collect whole mammary fluid. Alternatively, a variety of solid phasedevices, including glass or plastic slides, membranes, filters, beadsand like media, are provided to receive or partition selected liquid orsolid fractions of the mammary fluid, to receive or partition cells orcellular constituents from the mammary fluid, or to receive or partitionpurified or bulk proteins, glycoproteins, peptides, nucleotides(including DNA and RNA polynucleotides) or other like biochemical andmolecular constituents from the mammary fluid. A wide variety of suchsample collection devices can be readily adapted for use within specificembodiments of the invention. These collection devices may be providedas a component of the breast pump (such as a removable fluid reservoiror nitrocellulose filter placed within the pump to directly receive orcontact the expressed mammary fluid as it is pumped), or may be providedseparately (for example as a non-integral membrane, filter, affinitycolumn or blotting material to which mammary fluid or mammary fluidcomponents are exposed to collect a biological sample for assaypurposes).

Although the foregoing invention has been described in terms of certainpreferred embodiments, other embodiments and applications will becomeapparent to those of ordinary skill in the art in view of the disclosureherein. Accordingly, the present invention is not intended to be limitedby the recitation of preferred embodiments, but is intended to bedefined solely by reference to the appended claims.

1. An intraductal fluid sampling system, comprising: a control unit; apatient interface unit; a control line extending between the controlunit and the patient interface unit; a closed recirculation flow path,extending along the control line and providing communication between afirst component carried by the control unit and a second componentcarried by the patient interface unit; and a disposable patientinterface carried by the patient interface unit, for contacting thepatient; wherein the disposable patient interface comprises a flexiblepolymeric membrane and a rigid support for maintaining patency undervacuum, attached to the flexible polymeric membrane.
 2. An intraductalfluid sampling system as in claim 1, wherein the first componentcomprises a reservoir.
 3. An intraductal fluid sampling system as inclaim 2, wherein the reservoir is removably carried by the control unit.4. An intraductal fluid sampling system as in claim 2, wherein the flowpath comprises a movable wall.
 5. An intraductal fluid sampling systemas in claim 2, wherein the reservoir comprises a compressible container.6. An intraductal fluid sampling system as in claim 1, wherein thesecond component comprises at least one inflatable bladder.
 7. Anintraductal fluid sampling system as in claim 6, comprising at least 4inflatable bladders.
 8. An intraductal fluid sampling system as in claim7, comprising at least 6 inflatable bladders.
 9. An intraductal fluidsampling system as in claim 7, wherein each bladder has an inflatedwidth of no more than about 3 inches and an inflated length of no morethan about 4 inches.
 10. An intraductal fluid sampling system as inclaim 9, wherein each bladder has an inflated width of no more thanabout 2 inches and an inflated length of no more than about 3 inches.11. An intraductal fluid sampling system as in claim 6, wherein eachbladder has an inflated thickness of no more than about 1 inch.
 12. Anintraductal fluid sampling system as in claim 11, wherein each bladderhas an inflated thickness of no more than about 0.75 inches.
 13. Anintraductal fluid sampling system as in claim 1, further comprising aheat exchange media contained within the closed recirculation flow path.14. An intraductal fluid sampling system as in claim 1, furthercomprising a heat source in the control unit.
 15. An intraductal fluidsampling system as in claim 14, wherein the heat source is removably inthermal communication with the first component.
 16. An intraductal fluidsampling system as in claim 15, further comprising a pump in the controlunit.
 17. An intraductal fluid sampling system as in claim 16, whereinthe flow path is positioned such that the pump applies compressive forceto the flow path.
 18. An intraductal fluid sampling system as in claim1, further comprising a support in the patient interface unit, forsupporting the second component in compressive contact with the patient.19. An intraductal fluid sampling system as in claim 18, wherein thesupport is adjustable.